I. Field of the Invention
This invention relates to the field of anti-adherent, i.e., non-sticking, materials for coming into contact with the epidermis such as medical dressings, hospital linens, surgical dressings, various types of bandages and so forth.
The anti-adherent materials made in accordance with this invention are especially useful for placement beneath the bodies of hospital patients due for prolonged bed-confinement. Patients suffering from serious injuries, in particular, widespread burns or wounds which heal only with considerable difficulty can benefit greatly from the application of the dressings of this invention.
II. Description of the Prior Art
It is known that cutaneous wounds covering a large body surface area are particularly difficult to heal and are highly subject to infection. The dressings or sheets coming into contact with such wounds often cause partial destruction of the epidermis resulting from removing the patient from the sheets or changing the patient's dressings. The risk of septicemia is particularly increased since the dressings are maintained about the would in a warm and wet condition due to the suppuration of the wound. Moreover, contact of long duration of sheets and patient's healthy epidermis can lead to the formation of scabs. It is also known that all of these phenomena are the source of pains which at times are very severe for the hospitalized.
In order to remedy the disadvantage resulting from the suppuration of wounds, exposure of the latter to air at ambient temperature is generally recognized as favorable but it is not always possible to do this with the materials now in existence due to their abrasive action against the epidermis during healing.
Various materials have been proposed to remedy these disadvantages and are presently being used in hospitals as materials for coming into contact with patients' body surfaces, as for example, non-woven sheets of absorbant fibers having a surface coating of a permeable resin such as polypropylene or a surface which has been aluminized by the deposition of a layer of aluminum powder.
These materials represent a significant improvement over the previously employed sheets and dressings made of natural or synthetic textiles, however, they possess the major disadvantage of not being sufficiently anti-adherent. As a result such materials still have a tendency to stick to injured epedermis, either during renewal of the skin by grafting or in the natural manner, and cause deterioration of the epidermis as a result of its being unavoidably torn away.
Moreover, these materials can be used only once since they are not washable or capable of being sterilized and thus their use is economically undesirable.